Thank you for sharing the details of your problem.
I have reviewed the situation and would like to reassure you that this issue is not the result of any action on your part. Microsoft has confirmed that this is an active service incident, and a dedicated team of engineers is currently working to resolve the matter.
Please find below the official summary provided in the Service Health dashboard:
Users may receive error messages when opening, setting, or deleting tasks in Microsoft Teams Issue ID: TM1230627 Service affected: Microsoft Teams Start time: February 11, 2026, 09:00 UTC Scope of impact: Users in the UK, Europe, and North America may have difficulty using the Tasks app in Teams. Any user hosted in these regions can experience the issue.
Root Cause: A recent service update implemented in the European infrastructure encountered unexpected errors. This caused the Tasks feature to degrade.
Current status: The engineering team identified the crash update as a potential cause and began rolling back the changes to the last stable version. They are currently monitoring the service's telemetry during the deprecation process and evaluating alternative repair methods.
Next steps: Microsoft engineers will continue to monitor the deprecation process to ensure the stability of the service. They also conduct deeper analyses to understand the source of the problem and verify additional remediation paths.
Please rest assured that Microsoft engineers are actively working to restore full functionality as quickly as possible. At this time, no action is required from your side.
I hope this information helps. If you have any additional questions, please feel free to let me know.
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